Chapter 4 - Polynomials - 4.6 Special Products - 4.6 Exercise Set - Page 276: 7

$t^5+7t^4-2t-14$

Using $(a+b)(c+d)=ac+ad+bc+bd$ or the product of $2$ binomials, the given expression, $ (t^4-2)(t+7) $, is equivalent to \begin{array}{l}\require{cancel} t^4(t)+t^4(7)-2(t)-2(7) \\\\= t^5+7t^4-2t-14 .\end{array}